Conversion of molten metals directly into alpha solid fabricated state



March 2 2, 1932. H. HARRIS 1,850,653

CONVERSION OF MOLTEN METALS DIRECTLY INTO A SOLID FABRICATED STATE Filed Jan. 28, 1931 2 Sheets-Sheet l A TTORNE) March 22,1932. N HARRIS 1,850,668

CONVERSION OF MOLTEN METALS DIRECTLY INTO A SOLID FABRICATED STATE Filed Jan. 28, 1931 2 Sheets-Sheet 2 I 27 28 Fig. 4,

-vn F133 I F 'I 1 n-n f l r 5 i ll. 26

24 25 INVENTOR Patented Mar. 22, 1932 PATENT OFFICE UNlTED STAT-ES- IHENRY HARRIS, 01

LONDON, sperm Application filed January 28, 1931, Serial No. 511,866, and in Great Britain January 29 1930.

This invention relates to the conversion of molten metals or alloys directly into a solid fabricated state and has particular reference to such conversion in the case of metals 5 or alloys of relatively low melting oint such as lead and lead alloys. The chiei object of the present invention is to provide an im proved method and apparatus for converting such metal or alloy directly from a molten 1 condition to a fabricated solid state such as represented by piping, sheets, or ribbon. According to the present invention a mass of the molten metal or alloy contained in a reservoir surrounds two stationary spaced members such as a casing and central core extending into the molten mass, and the metal or alloy entering between the core and casing is advanced in successive portions by a third member or ram operating in the intervening space which comprises two accurately temperature controlled zones, the foremost being located just beyond the forward limit of movement of the ram and maintained at a temperature such that the metal or alloy enters in a pasty or incipient solidifying state and leaves as a solid extruded article whilst the other and rearwardly adjacent zone coincident with the forward part of the ram movement is maintained at a temperature such that the portion of molten metal or alloy entering into contiguity with the preceding portion when the ram recedes is cooled to a pasty or semi-solidified ap- O pendage state so that under the pressure of the ram at its next advance both portions of the metal or alloy will be advanced without any shearing effect, but on the contrary by a plain compressing and extruding action so that the product is necessarily very uniform in character and verystraight in form.

In order to ensure accuracy of dimensions of the extruded article the casing may be internally shaped as or be provided with a die from which the metal oralloy is extruded; also in order to provide arelief in the event of excessive extrusion pressure on the entrapped metal being exerted by the ram,'the latter may be longitudinally grooved so that r some of the pasty metal or alloy just at-the rear of the ram face can under excess pressure escape rearwardly along the grooves and ini cidentally assist the free movement of the ram by a quasi-lubricating action. In the preferred construction the molten metal enters the annular space between the ram and the casing by way of submerged apertures in the casing uncovered by the ram when it recedes.

Owing to the aforesaid temperature-controlled zones or spaces being stationary the temperature can be easily and accurately controlled as for'ex'ample by providing a hollow space or jacketin or around either or both members and by circulating air, water, oil or other fluid therein at a predetermined temperature.

The following description'and drawings have reference to a convenient constructional form the invention may take.

In the drawings Figure 1 is a front sectional elevation of a compression unit comprising essentially a core, a casing and a ram adapted in accordance with the present invention for operation within a bulk of molten metalor alloy contained in a tank or reservoir.

Figure 2 is a partial sectional elevation, viewed from the same aspect as Figure 1, of the reservoir and supply-regulating apparatus. 8

Figure 3 is a detail view, taken at right angles to Figures 1 and 2. of the adjustment for maximum height of liquid level in the reservoir.

Figure 4 is a front elevation of the apparatus showing three units positioned in the reservoir. 7

As seen in Figure 1 the unit comprises a short cylindrical hollow die 1 and a long core 2 positioned concentrically within a casing 3. The latter is externally threaded from approximately the level of the die 1 to its lower extremity and carries at and below the level of said die an annular cooling jacket 4 which can be turned tottake up any desired 95 position along the casing 3 and be locked in such position as by lock-nuts 5. This jacket is provided with inlet and outlet fluid pipes 6 and 7. The lower extremity of the core 2 is secured to the lower end of a frame 8, and

its upper end lies near to or just beyond the top level of the die. The upper end of the frame 8 receives the threaded end of casing 3.

The die 1 is a sliding fit in the casing 3 and is positioned therein by upper and lower sleeves 9 and 10-, these three elements together lining the entire length of easing 3. The

sleeves 9 and 10 are of slightly larger in-' latter as by a pin 12 projecting upwards from a flange on the sleeve 10 into a slot on the lower edge of the casing 3.

The ram 13 is in the form of a cylindrical sleeve adapted to slide into and out of the annular space above referred to and has 1ongitudinal grooves with or without cavities as shown to allow excess metal to escape rearwardly and to facilitate free action of the ram. This ram 13 is attached, at its lower extremity within the frame 8, to a stout channel-section cross member 14. This cross member extends beyond the frame 8 (see Fig. 4) and is attached to vertical rods 15. These latter extend upwardly to overhead cranks or like reciprocating driving means (not shown).

The action of the device is as follows The unit represented in Figure 1 is immersed to a suitable depth in he molten metal in a reservoir 18, such for example as that indicated b the dotted line 16 (Fig. 1). Upon with rawing the ram 13 to its lowest position, molten metal enters by the apertures 11 and commences to solidify in the space around the core 2. The temperature at the die and just below itis such that the metal at the entrance to the die and just below it is in a pasty state whilst the metal at the exit of the die is truly solid so that as the ram ascends the metal is compressed and moulded in the die entrance without requiring great pressure but nevertheless emerges from the die as an extruded solidified tube.

When the ram recedes fresh molten metal enters the space below the die and becomes a pasty metallic appendage to the metal actually in the die, and on the next ascent of the .ram this appendage is driven into the die space.

The net result is that as the ram 13 is reciprocated a continuous length of extruded solid metal tube emerges from the die and eventually from the top of tube 3.

As seen in Figure 2, the molten metal 17 enters the reservoir 18 by a vertical pipe 19 and a horizontal perforated pipe 20. The pipes are joined by a universal oint 21 and the pipe 20 is supported at its ree end and may have its inclination altered by an adj ustable vertical rod 22.

Situated within the pipe 19 is an admission valve 23. This valve is automatically regulated by rod connection 24 with a float 25. This float is carried by a frame 26 (see Fig. 3) which frame is threaded on a screwed portion of the rod 24. The upper extremity of rod 24: is revolubly carried in a fixed-collar 27 to which the frame 26 is slidably but not revoiubly attached by the pin and slot connection 28. It will thus be seen that by rotating the rod 24 by the handle 29 the frame '26 and float 25 may be adjusted vertically,

causing a corresponding change in the level of the molten metal.

A draining outlet 30 is provided at the lowest point of the reservoir, and is normally closed by a raisable plug 31. The reservoir slopes towards this outlet toensure that draining shall be complete. The reservoir is lagged in any well known manner (not shown) and during operation is maintained heated by any convenient means (not shown), and is preferably so mounted as to be capable of vertical movement, whereb it may be lowered clear of the casting unit or units when de-. y

sired.

adjustment by moving the retaining nuts 5, and employs oil, water, air or other suitable cooling fluid.

It is also to be noted that the arrangement of sleeves 9 and 10 and die 1 prevents the possibility of the casing 3 becoming internally corroded or damaged and also allows of easy replacement of the die itself. The sleeve 9 is of slightly lar er diameter than the die 1 so that the pro uct ascending the sleeve is not frictionally retarded but is nevertheless guided in its ascent for some distance beyond the die.

Although one embodiment of the invention has been described it is tobe understood that various modifications may be resorted to within the scope of the invention. For example, the cooling medium in the solidification zone may be passed into the core 2 instead of around the casing 3 or both modes of cooling may be adopted, and the core 2 The cooling jacket 4 is capable of vertical itself may be vertically adjustable. More- .over although the apparatus above described example the casing might be square and the core be rectangular to fit the square in one direction but be narrower in the other direction, whereby two strips of metal or alloy could be formed simultaneously by a suitably forked ram. Also by providing means to cause the pipe to emerge in slit form and then become spread flat, the resultant metal is in sheet form.

The power for driving the ram in apparatus as above described may be of any convenient form and preferably, as the effort to be exerted is irregular, two or more rams are coupled to a single driving shaft for mechanical balancing purposes.

lVhat I claim is 1. Method of converting molten material of relatively low melting point directly into solidified fabricated articles consisting in admitting the material in successive portions between stationary spaced members extending into a molten mass of said material, and advancing the admitted material by athird member in the form of a ram operating in the said space while maintaining predetermined temperatures at two adjacent zones in said space, the foremost zone being located just beyond the forward limit of movement of the ram and maintained at a temperature such that the material enters in a pasty or incipient solidifying state and leaves as a solid extruded article whilst the other and rearwardly adjacent zone coincident with the forward part of the ram movement is maintained at a temperature such that the portion of molten material entering into contiguity with the preceding portion when the ram recedes is cooled to a pasty or semi-solidified appendage state.

2. Apparatus for converting molten material of relatively low melting point directly into fabricated solid articles, comprising relatively stationary spaced members one of which is provided with meanspermitting entrance of surrounding molten material to an intervening space, a movable ram operating in the intervening space, an internal pressure-shaping die located just beyond the limit of movement of the ram, and means so controlling the temperature of the shaping space and below the die and in the region of entrance that the molten material enters the shaping space in a pasty or incipient solidifying state and leaves as a solid extruded article whilst the metal in the region of the forward part of the ram movement is maintained at a temperature such that the portion of molten material entering into contiguity with the preceding portion when the ram recedes is cooled to a pasty or semisolidified appendage state.

3. Apparatus as claimed in claim 2 the temperature-controlling means comprising a cooling jacket provided with means for its adjustment longitudinally of said spaced members.

4. Apparatus as claimed in claim 2 the relly perforated 6. Apparatus as claimed in claim 2, the v pressure-shaping die being positioned at least partly below the surface of molten material contained in a reservoir. I

7. Apparatus as claimed in claim 2 in which means of access of the molten material to the space below the pressure-shaping die are provided by apertures in a part of the outer one of the spaced members submerged in the molten material and uncovered by the ram in its descent.

8. Apparatus for converting molten material of relatively low melting point directly into solid pipe, comprising a reservoir, a stationary cylindrical casing having a partportion' immersed in a vertical position in a bulk of the molten material contained in the reservoir, a stationary cylindrical core extending upwards axially within said casing to a point near to and preferably somewhat above the level of the molten material, a hollow cylindrical ram reciprocatable in the annular space between casing and core, a pressure-shaping die located in the casing just beyond the top limit of movement of the ram, and means for maintaining the material in the space within the aforesaid die and the adjacent space surrounding the highest point to which the ram ascends at a temperature such that each of the successive portions of the molten material entering the casing at each descent of the ram becomes a pasty or semi-solidified appendage to the preceding portion within the die, so that the latter portion is still in a pasty condition at the entrance to the die butis in a solid extruded condition at the exit from the die.

9. Apparatus as claimed in claim 8including a removable sleeve located between the casing and core, and perforated similarly to said casing.

10. Apparatus as claimed in claim 2, the

ram being longitudinally grooved.

In testimony whereof I have signed my name to this specification.

- HENRY HARRIS. 

